Method for preventing soy sauce from putrefaction

Abstract

A method for preserving soy sauce which comprises admixing therewith acetic acid and a salt of acetic acid, propionic acid, butyric acid, malic acid, tartaric acid, citric acid or lactic acid. The amount of the acid salt is in excess of the amount of acetic acid. The method provides a sufficient antiseptic effect without producing a sour taste and without greatly lowering the pH.

What is claimed is: 
     
       1. A method for preventing soy sauce from spoiling comprising adding to raw uncooked soy sauce before or after sterilization, a preservative solution in an amount sufficient to prevent the soy sauce from spoiling, said preservative solution consisting essentially of (a) acetic acid and (b) a salt selected from the group consisting of the sodium salt, the potassium salt, and the calcium salt of an organic acid selected from the group consisting of acetic acid, malic acid, tartaric acid, citric acid, and lactic acid, said preservative solution being added in an amount such that the content of acetic acid in the soy sauce is between 0.02 and 0.2 percent by weight, and said preservative solution containing an amount by weight of said salt which is in excess of the amount of acetic acid up to 6 times the amount of acetic acid. 
     
     
       2. The method of claim 1 wherein said preservative solution is prepared by adding at least one material selected from the group consisting of egg shell, sodium bicarbonate, and sodium hydroxide to vinegar, whereby when said material which is added to said vinegar is only egg shell or sodium bicarbonate, it is added in an amount between 0.6 and 1.1 parts per part of acetic acid, and when it is sodium hydroxide, it is added in an amount between 0.29 and 0.53 parts per part of acetic acid, whereby the amount of acetate formed by the reaction of said material and acetic acid in the vinegar is larger than the amount of acetic acid present. 
     
     
       3. The method of claim 1 or claim 2 wherein the preservative solution contains between 2 and 6 times by weight of said salt as said acetic acid. 
     
     
       4. The method of claim 3 wherein said acid salt is an acetate.